JP4373991B2 - Golf club shaft selection system and golf club shaft selection method - Google Patents

Description

  The present invention relates to a golf club shaft selection system and a golf club shaft selection method, and more particularly to a golf club shaft selection system and a golf club shaft selection method for selecting a golf club shaft suitable for the golfer according to the golfer's swing characteristics. .

  A golf club shaft has various characteristics, and a golfer needs to select a golf club shaft having characteristics suitable for the golf club shaft. Of the various characteristics of the golf club shaft, it is possible to select a club shaft suitable for each golfer in most cases by appropriately selecting the shaft mass, the flex and the shaft condition (FLEX POINT). However, since the shaft mass, flex and shaft tone can be designed independently, there are innumerable combinations thereof, and it is not easy to select a golf club shaft suitable for each golfer. There wasn't.

  An example of a golf club shaft selection system focusing on shaft flex (EI: flexural rigidity) is described in Japanese Patent No. 3061640. Here, it is possible to measure any of the golfer's swing time, swing speed (club head speed), club head acceleration and shaft distortion, or to measure the above measurement items and head speed. It is disclosed.

  Moreover, as a golf club shaft selection system paying attention to the bending rigidity distribution (EI distribution) of a shaft, what was described in Unexamined-Japanese-Patent No. 2004-129687 is mentioned. Here, the shaft behavior measuring means for measuring the deformation behavior of the shaft during the swing, the shaft EI calculation means for calculating the EI distribution of the shaft, and the shaft shape calculation means for calculating the deformation shape of the shaft during the swing are provided. 1 analysis system and a second analysis system having a swing classification means for analyzing and classifying a golfer's swing, analyzing the deformation behavior of the shaft during the swing, classifying the golfer's swing, and It is disclosed to select an optimum shaft.

  Moreover, as a golf club shaft selection system paying attention to the torsional rigidity (torque) of a shaft, what was described in Unexamined-Japanese-Patent No. 2001-70482 etc. is mentioned. Here, it is disclosed that the amount of distortion of the shaft during the swing of each golfer is measured or the head speed is measured simultaneously with the amount of distortion.

  Other examples of the method for measuring torsional strain include those described in JP-A-2003-205053. Here, it is disclosed that torsional distortion generated in a shaft during a swing of a golf club is measured, and dynamic evaluation of the shaft including the torsional behavior of the shaft is performed based on time history data of the measured torsional distortion.

  Moreover, as a golf club shaft selection system which paid attention to the amount of toe down at the time of a swing, what was described in Unexamined-Japanese-Patent No. 2003-284802 etc. is mentioned. Here, the bending moment distribution applied to the shaft when the sample golf club is swung is measured, and from the measured data and the bending rigidity distribution of the shaft, the shaft head in the direction in which the toe side of the club head is lowered immediately before the impact is measured. There is disclosed a method of calculating five elements including a “toe down amount” that is a deflection amount, and selecting a shaft that is more appropriate or optimal for a golfer based on the calculation result.

Another example of the method for measuring the “toe down amount” is that described in Japanese Patent No. 3549334. Here, it is disclosed that a television camera or optical detection means is used when measuring the toe down amount of a golf club.
Japanese Patent No. 3061640 JP 2004-129687 A JP 2001-70482 A JP 2003-205053 A JP 2003-284802 A Japanese Patent No. 3549334

  However, when a golfer selects a golf club (shaft), no clear selection criteria have been obtained so far regarding the selection of the mass and shaft tone (EI distribution) of the golf club shaft.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a golf club shaft selection system and a golf club that enable selection of a golf club shaft having an appropriate shaft mass and shaft tone. It is to provide a shaft selection method.

  The golf club shaft selection system according to the present invention includes a head speed detecting unit that detects a head speed at the time of impact in a golfer's swing, and a swing tempo detecting unit that detects a swing tempo of the golfer.

In the present specification, “swing tempo” means the swing tempo of each golfer . In the present invention, the swing tempo, maximum deflection of the shaft in the swing, i.e., Ru is evaluated based on the maximum amount of displacement of the tip relative to the shaft proximal part.

In one aspect, the golf club shaft selection system includes a chart showing a preferable shaft condition according to a head speed and a swing tempo, and a head detected by a head speed detection unit and a swing tempo detection unit while referring to the chart. Selection means for selecting a golf club shaft suitable for the golfer based on the speed and swing tempo, and display means for displaying the golf club shaft selected by the selection means are further provided.

  According to the above configuration, a golf club shaft having a shaft tone suitable for each golfer is selected.

  Generally, the shaft tone is expressed by the expression of the first, middle, and hand (original) tone, depending on which portion the shaft is liable to bend. In other words, it can be said that the balance of the bending rigidity value of each part of the shaft affects the shaft tone.

Here, the shaft tone classification in the chart is based on the average value of the bending rigidity value of the central portion of the shaft of the golf club shaft and the bending rigidity value of the club shaft at the tip portion located on the club head side with respect to the central portion of the shaft. The tip of the shaft relative to the average value of the bending rigidity value of the central part of the shaft is determined based on the relationship between the average value and the average value of the bending rigidity value of the club shaft at the hand part located on the grip side with respect to the central part of the shaft. The ratio of the average value of the bending stiffness of the shaft and the ratio of the average value of the bending stiffness value of the proximal portion to the average value of the bending stiffness value of the central portion of the shaft are performed.

  In the present specification, the “club shaft” is typically a club shaft for a driver. In this case, the “tip portion” of the club shaft means a portion having a distance of 50 mm or more and 150 mm or less from the tip of the club shaft (end portion on the club head side), and the “shaft center portion” is the distance from the tip of the club shaft. Means a portion where the distance from the tip of the club shaft is 800 mm or more and 1100 mm or less. However, the idea of the present invention can be applied to all golf clubs other than the driver. In this case, the “tip portion” of the club shaft means a portion whose distance from the tip of the club shaft is 100 mm ± 50 mm, and the “shaft center portion” is the longitudinal center of the club shaft (when the club head is mounted) ± 150 mm. The “hand portion” means a portion whose distance from the grip end of the club shaft (when the club head is mounted) is 150 mm ± 150 mm.

In another aspect, the golf club shaft selection system includes a first chart showing a preferable shaft mass according to the head speed and the swing tempo, and a second chart showing a preferable shaft condition according to the head speed and the swing tempo. The selecting means for selecting a golf club shaft suitable for the golfer based on the head speed and the swing tempo detected by the head speed detecting means and the swing tempo detecting means with reference to the first and second charts, and the selecting means Display means for displaying the selected golf club shaft is further provided.

  According to the above configuration, a golf club shaft having a shaft mass and a shaft tone suitable for each golfer is selected.

  In addition, said 1st and 2nd chart may be provided separately and may be provided as an integral chart.

Here, the shaft tone classification in the second chart is the average value of the bending rigidity value of the central portion of the shaft of the golf club shaft and the bending rigidity of the club shaft at the tip portion located on the club head side with respect to the central portion of the shaft. Is performed based on the relationship between the average value of the values and the average value of the bending stiffness value of the club shaft at the grip portion located on the grip side with respect to the shaft center portion, This is performed using the ratio of the average value of the bending rigidity value of the tip part and the ratio of the average value of the bending rigidity value of the proximal part to the average value of the bending rigidity value of the central part of the shaft.

Te golf club shaft selecting system Odor described above, swing tempo detecting means detects the swing tempo golfer based on the maximum amount of deflection of the shaft in the swing.

As a result, a more accurate swing tempo can be detected.
The golf club shaft selection system described above preferably further comprises another chart showing a preferred flex depending on head speed and swing tempo. And a selection means refers to another chart when selecting the golf club shaft suitable for a golfer.

  This selects a golf club shaft having a preferred flex in addition to a preferred shaft mass / shaft tone.

  In the above golf club shaft selection system, “selecting a golf club shaft suitable for the golfer” includes “selecting a golf club suitable for the golfer”, and “displays the selected golf club shaft. "Includes" displaying the selected golf club ".

  The golf club shaft selection method according to the present invention includes a step of detecting a head speed at impact in a golfer's swing and a swing tempo of the golfer.

In one aspect, the golf club shaft selection method further includes a step of selecting a golf club shaft having a shaft tone suitable for a golfer based on the detection result of the detection step.

  According to the above configuration, a golf club shaft having a shaft tone suitable for each golfer is selected.

In another aspect, the golf club shaft selection method further includes a step of selecting a golf club shaft having a shaft mass and a shaft tone suitable for a golfer based on the detection result of the detection step.

  According to the above configuration, a golf club shaft having a shaft mass and a shaft tone suitable for each golfer is selected.

The Te golf club shaft selecting method odor, classification kick is the average value of the flexural rigidity of the shaft center portion of the golf club shaft, of the club shaft at the distal end portion located on the club head side with respect to the shaft center portion This is based on the relationship between the average value of the bending stiffness and the average value of the bending stiffness value of the club shaft at the grip portion located on the grip side with respect to the central portion of the shaft. The ratio of the average value of the bending stiffness value of the tip portion to the value and the ratio of the average value of the bending stiffness value of the proximal portion to the average value of the bending stiffness value of the central portion of the shaft are performed.

The Te golf club shaft selecting method smell, detects the swing tempo golfer based on the maximum amount of deflection of the shaft in the swing.

  In the golf club shaft selection method, the selection step preferably includes a step of selecting a golf club shaft having a flex suitable for the golfer based on the detection result of the detection step.

  This selects a golf club shaft having a preferred flex in addition to a preferred shaft mass / shaft tone.

In the golf club shaft selection method, “selecting a golf club shaft suitable for a golfer” includes “selecting a golf club suitable for a golfer”.

  According to the present invention, clear selection criteria for the mass and tone of a golf club shaft can be obtained.

  Embodiments of a golf club shaft selection system and a golf club shaft selection method according to the present invention will be described below.

  FIG. 1 is a block diagram showing the configuration of a golf club shaft selection system according to one embodiment of the present invention. Referring to FIG. 1, a golf club shaft selection system according to the present embodiment includes a head speed detection unit 100 that detects a head speed at the time of impact in a golfer's swing, and a swing tempo detection unit that detects a golfer's swing tempo. 200. The head speed detection unit 100 and the swing tempo detection unit 200 are included in the swing analysis apparatus 1 described later.

  The golf club shaft selection system is detected by the head speed detection unit 100 and the swing tempo detection unit 200 with reference to the chart 300 showing the shaft mass and shaft condition corresponding to the swing characteristics of each golfer, and the chart 300. A selection unit 400 for selecting a golf club shaft suitable for a golfer based on the head speed and swing tempo, and a display device 500 for displaying the golf club shaft selected by the selection unit 400 are further provided. Here, the chart 300 is a first chart 310 showing a preferable shaft mass according to the head speed and swing tempo of each golfer, and a first shaft tone showing a preferable shaft condition according to the head speed and swing tempo of each golfer. 2 chart 320 and a third chart 330 (another chart) showing a preferred flex according to the head speed and swing tempo of each golfer.

  The chart 300 is stored in a hard disk of a computer, for example. As the selection unit 400, for example, a computer having a CPU is used. The display device 500 connected to the selection unit 400 may be a display device or a printer device.

  Information from the swing analysis device 1 is input to the selection unit 400. The selection unit 400 classifies the swing characteristics of each golfer based on the analysis result by the swing analysis apparatus 1 with reference to the chart 300, and based on the classification result, the shaft mass and shaft suitable for each golfer. A golf club shaft having a tone is selected. The selection result is displayed on the display device 500.

  The chart 300 may be a panel illustrating the relationship between the head speed / swing tempo and the preferable shaft mass / shaft condition. Further, instead of the selection unit 400, a “person” may select a preferable shaft.

  FIG. 2 is a block diagram showing a configuration of the swing analyzing apparatus shown in FIG. Referring to FIG. 2, swing analysis apparatus 1 analyzes a swing when golfer 2 hits ball 4 using golf club 3. The swing analysis apparatus 1 includes high-speed cameras 1A and 1B, a high-speed video tape recorder 1C, metahexalite 1D, a strobe power supply 1E, and a strobe 1F.

The high speed camera 1A photographs the ball 4 from the front. Moreover, the high speed camera 1B images the golfer 2 overhead from the front side of the body. The number of frames of the high-speed cameras 1A and 1B is 1/200 sec, for example. The outputs of the high speed cameras 1A and 1B are recorded by the high speed video tape recorder 1C. In order to illuminate the golfer 2 and the ball 4, metahexalite 1D is used. Further, a strobe 1F connected to a strobe power source 1E is provided to illuminate the golfer 2 with a strobe. The strobe 1F is activated by the strobe power source 1E and emits light before the golfer 2 starts swinging. The strobe 1F is activated when the recording button of the high-speed video tape recorder 1C is pressed.

  The high-speed video tape recorder 1C is connected to a display device 500 that is a display device via a selection unit 400 that is a computer having a CPU. Then, the image recorded on the high speed video tape recorder 1C is displayed on the display device 500.

  Next, the operation of the swing analysis apparatus 1 will be described. First, the recording button of the high-speed video tape recorder 1C is operated, and the recording is disclosed. At that time, the strobe 1F emits light from the strobe power supply 1E. When the golfer 2 swings the golf club 3, the high-speed camera 1A captures an image near the ball 4, and the high-speed camera 1B captures an image near the top of swing (position where the club head rests on the golfer's head). Taken. Images taken by the high speed cameras 1A and 1B are recorded by the high speed video tape recorder 1C. When swinging again, the high-speed video tape recorder 1C is temporarily stopped and the same operation is repeated. When the swing measurement is finished, recording by the high speed video tape recorder 1C is stopped.

  Next, the tape is rewound and an image recorded on the high-speed video tape recorder 1C is reproduced on the display device 500. Then, the swing start time and the impact time are detected by the frame advance operation. Thereby, the “swing time” from the start of the swing to the impact is detected. The “swing time” is an index indicating the “swing tempo”. Further, the head speed at the time of impact can be detected by the frame advance operation.

  FIG. 3 is a view showing the motion of the golf club near the top of swing by frame advance (at intervals of 0.01 seconds). The image shown in FIG. 3 is taken by the high speed camera 1B. Referring to FIG. 3, golf club 3 is positioned at “A2” 0.1 seconds before the top of swing time, moves in the direction of arrow DR1, and then reaches top of swing position “A1”. Thereafter, the golf club 3 moves in the direction of the arrow DR2 toward the impact position.

  By analyzing the image shown in FIG. 3, it is possible to detect the club head moving speed (“swing speed”) a predetermined time before the top of swing (for example, 0.08 seconds before). Similarly, club head acceleration (“swing acceleration”) in the vicinity of the top of swing can be detected. “Swing speed” and “swing acceleration” are one index indicating “swing tempo”.

FIG. 4 is a block diagram showing a configuration of a modification of the swing analyzing apparatus shown in FIG. 5 is a view showing a golf club used for swing analysis in the swing analysis apparatus shown in FIG. 4, and FIG. 6 is a view showing a VI-VI cross section in FIG. Referring to FIG. 4, the swing analysis apparatus 1 according to this modification includes a strain gauge 1G attached to the club shaft 5, a bridge box 1H, and an amplifier 1I. As shown in FIG. 5, the strain gauges 1 </ b> G are respectively provided at a plurality of strain gauge attaching positions 10 </ b> G to 13 </ b> G provided in the length direction of the club shaft 5. Further, as shown in FIG. 6, the strain gauge 1G is attached to the side surface of the club shaft 5 in the flying ball direction (x-axis direction) and the side surface in the direction orthogonal to the flying ball direction (y-axis direction). . A deflection amount of the golf club shaft 5 is obtained from a combined strain amount obtained by combining the strain amount in the x-axis direction and the strain amount in the y-axis direction. It should be noted that only one strain gauge attaching position for attaching the strain gauge 1G may be provided in the length direction of the club shaft 5. In the present embodiment, a strain gauge is provided at a position of about 14 inches (about 360 mm) from the grip side end.

  Referring again to FIG. 4, the strain gauge 1G detects the strain amount of the club shaft 5 during the swing. The detected distortion amount is sent to the selection unit 400, which is a computer having a CPU, via the bridge box 1H and the amplifier 1I, and is displayed on the display device 500. Thereby, the change of the deflection amount of the club shaft 5 during the swing is measured. The amount of deflection of the club shaft 5 is maximized in the vicinity of the top of swing. The “maximum deflection amount” is an index indicating “swing tempo”. In general, a preferable “maximum deflection amount” during the swing is about 70 to 130 mm (more preferably about 100 mm).

  The “maximum deflection amount” is the maximum displacement amount of the tip portion with respect to the shaft proximal portion. Here, the maximum amount of displacement of the tip portion relative to the hand portion was calculated with the portion from the grip side end portion to the length (about 7 inches, about 180 mm) generally gripped by the golfer as the hand portion.

  As described above, in the golf club selection system according to the present embodiment, the maximum deflection amount of the shaft during the swing, the swing time, the club head speed (swing speed) a predetermined time before the top of swing, and the vicinity of the top of swing The swing tempo of the golfer is detected based on any of the club head accelerations (swing accelerations). When any of the above parameters is used, the “swing tempo” necessary for selecting the golf club shaft can be accurately detected.

  FIG. 7 is a flowchart illustrating a golf club shaft selection method according to one embodiment of the present invention. Referring to FIG. 7, at S10, the head speed and swing tempo at the time of impact in the swing are measured. The measurement is performed using, for example, the swing analysis apparatus 1 shown in FIGS.

  Next, in S <b> 20, the golfer's swing characteristics are classified based on the measurement result by the swing analysis device 1. That is, it is determined to which group of the plurality of groups prepared in advance the head speed and swing tempo of the golfer.

  In S30, a club shaft corresponding to the golfer's golfer's swing characteristics (head speed and swing tempo) is selected based on the classification result. At this time, a first chart 310 showing a preferable shaft mass according to the head speed and the swing tempo at the time of impact, a second chart 320 showing a preferable shaft tone according to the head speed and the swing tempo at the time of impact, Reference is made to a chart 300 having a third chart 330 showing a preferred flex depending on the head speed and swing tempo at impact. Note that the number of golf club shafts selected in S30 may be one or a plurality (for example, two to three).

  Note that the classification step of S20 can be omitted. That is, the selection step in S30 may be performed based on the measurement result in S10.

  Subsequently, in S40, a trial hit is made using a golf club having the selected club shaft. In S50, the golf club that made the trial hit is evaluated. Here, for example, objective data such as “head speed”, “ball speed”, “meet rate”, “ball spin amount”, “flying angle”, “variation in hitting position”, “ballistic variation” and The golfer's sense of “easy to take timing / difficult to take timing” and “easy to swing / difficult to swing” can be used as a criterion for evaluation.

Here, an example of the evaluation method in S50 will be described.
The “variation in hitting position” can be detected by, for example, applying a so-called “face seal” that changes the color of the portion that the ball contacts at the time of hitting the ball to the face portion of the club head.

Further, when evaluating using the “meet rate”, the following method is used.
The meet ratio (= ball initial speed / head speed) is a desired characteristic that is higher as it is higher. When the i-th meat rate is yi, the SN ratio (η) of the meet rate yi (i = 1 to n) is obtained by the following equations 1 and 2.

  Table 1 shows an example of the meat ratio and the S / N ratio when trial hits are performed three times each using club shafts having masses of 50 g, 60 g, and 70 g.

  In the example shown in Table 1, the SN ratio is the highest when the shaft mass is 60 g. Therefore, it is judged that a club shaft with a mass of 60 g is the best.

The above contents are summarized as follows. That is, in the golf club shaft selection method according to the present embodiment, the step (S10) of detecting the head speed at the time of impact in the golfer's swing and the swing tempo of the golfer, and the golfer's swing based on the detection result of the detection step Are classified (S20), and a golf club shaft having a shaft mass and a shaft tone suitable for the golfer is selected based on the classification result of the classification step (S30).

  The inventors of the present application have confirmed that a certain relationship is found between a golfer's swing type (head speed and swing tempo at impact) and a shaft mass and shaft tone suitable for the golfer. Therefore, according to the club shaft selection method, an objective selection criterion can be obtained regarding the shaft mass and the shaft condition. As a result, it becomes possible to select a golf club more suitable for each golfer.

  Further, the inventors of the present application select a shaft tone according to the swing characteristics of each golfer, and determine the club shaft bending rigidity value at the central portion in the length direction (shaft central portion) and the clubs at the hand portion and the tip portion. It is confirmed that the relationship with the bending stiffness value of the shaft is closely related. Therefore, the classification of the shaft condition to be selected is the relationship between the bending rigidity value of the central portion of the shaft of the club shaft, the bending rigidity value of the club shaft at the tip portion, and the bending rigidity value of the club shaft at the proximal portion. By performing based on this, it is possible to select a shaft tone more suitable for each golfer.

  In the present embodiment, the chart 300 includes a first chart 310 showing a preferable shaft mass according to the head speed and the swing tempo at the time of impact, and a preferable shaft condition according to the head speed and the swing tempo at the time of impact. In the above description, the chart 300 is mainly described with reference to the second chart 320 and the third chart 330 showing a preferred flex according to the head speed and swing tempo of each golfer. Only the charts 310 and 320 may be included, only the first chart 310 may be included, or only the second chart 320 may be included.

  When the chart 300 includes the first to third charts 310, 320, and 330, selection of a club shaft having a shaft mass, a shaft tone, and a flex suitable for each golfer can be supported. When the chart 300 has only the first and second charts 310 and 320, selection of a club shaft having a shaft mass and a shaft tone suitable for each golfer is supported. In addition, when the chart 300 has only the first chart 310, selection of a club shaft having a shaft mass suitable for each golfer is supported, and when the chart 300 has only the second chart 320, each golfer Selection of a club shaft having a suitable shaft tone is supported.

  In addition, it is preferable to use what has the same club head, the same head mass, the same length, and the same grip as a plurality of trial hit clubs used for the test hit of S40 mentioned above. Thereby, the golf club suitable for each golfer can be selected by selecting the club shaft suitable for each golfer.

  FIG. 8 is a diagram showing the outer diameter and bending stiffness distribution (EI distribution) of a golf club shaft used in the golf club shaft selection method according to one embodiment of the present invention. The horizontal axis in FIG. 8 indicates the distance from the club head side end of the golf club shaft. In the example of FIG. 8, the outer diameter and bending rigidity of the golf club shaft increase from the club head side toward the grip side.

  FIG. 8 shows data of three club shafts (butt standard / butt stiff / butt soft) that have the same EI distribution but exhibit the same amount of deflection in the cantilever model. Details of the “cantilever model” and “butt standard / butt stiff / butt soft” will be described later.

Below, the measuring method of the bending rigidity distribution of a golf club shaft is demonstrated.
The bending stiffness value can be obtained by the following calculation formula from the displacement-load inclination in the three-point bending test.
EI = (W / δ) × L 3/48
EI: Flexural rigidity value, W: Load, δ: Deflection amount (displacement) of load point, L: Span (distance between fulcrums)
Various conditions in the three-point bending test conducted by the inventors of the present application are as follows.

  The fulcrum is R10 (radius 10mm), the distance between the fulcrum: span L is set to 200mm, the load point is R75mm (radius 75mm) indenter jig (made of iron), the center part between fulcrum Set to load. The test speed is 2 mm / min, and W / δ is data of deflection amount change (displacement) when the load is 10 kgf (98 N) to 20 kgf (196 N). Thereby, the bending rigidity value of the load point is obtained. The bending stiffness distribution is obtained by repeating the measurement by moving the load point.

On the other hand, the measurement of the bending stiffness value by a four-point bending test is effective when the wall thickness is thin relative to the outer diameter (particularly at the hand). In the case of a four-point bending test, the bending stiffness value is calculated by the following equation.
EI = (W / δ) × (a / 48) × (3L ² −4a ² )
EI: Flexural rigidity value, W: Load (However, there are two load points, each load is W / 2), L: Span (distance between fulcrums), δ: Central part of span (central part between fulcrums) Deflection amount (displacement), a: distance from one fulcrum to the adjacent load point, (La) / 2: distance between two load points Various values in the four-point bending test conducted by the inventors of the present application The conditions are as follows:

  The fulcrum is R75 (radius 75mm), the load point is R75mm (radius 75mm) indenter jig (made of iron), the distance between the fulcrum: span L is set to 300mm, and two load points The distance between them was set to 130 mm, that is, the distance from the fulcrum on one side to the adjacent load point: a was set to 85 mm. The test speed is 2 mm / min, and W / δ is data of deflection amount change (displacement) when the load is 15 kgf (147 N) to 20 kgf (196 N). Thereby, the bending rigidity value of the center part of two load points is calculated | required. The bending stiffness distribution is obtained by repeating the measurement by moving the load point.

In addition, a strain gauge in one direction is attached to the longitudinal direction of the golf club shaft at the position where the bending rigidity value is to be measured, the grip portion of the shaft is fixed, and the strain changes when a load is applied to the head side of the shaft. There is also a method of calculating the bending stiffness value EI by measuring ε. In this case, the bending stiffness value is calculated by the following equation.
EI = (W × L) × (d / 2) / ε
EI: bending stiffness value, W: load, L: distance from the strain measurement position to the load point, d: outer diameter of the strain measurement position, ε: strain amount Test using a strain gauge conducted by the inventors The following are the conditions.

  First, a strain gauge is affixed at a position where the bending stiffness value is to be measured. Next, 50 mm on the grip side of the shaft is fixed with a cylindrical chuck (three-claw chuck) so that the strain gauge is on the upper surface. The load point is applied from the position of the strain gauge to the position of the head side L of the shaft: 700 mm. As a loading method, a weight of W: 1 kgf (9.8 N) is suspended. The output value of the strain gauge before and after the weight is suspended is used as the strain amount ε. The outer diameter d of the strain measurement position is measured separately.

  FIG. 9 is a diagram showing the distribution of head speed and swing tempo (maximum amount of deflection of the club shaft during a swing) detected by the detection step in the golf club shaft selection method according to the present embodiment. In this example, measurement was performed using a golf club (driver and 6 iron) having a golf club shaft having an outer diameter and a bending stiffness distribution shown in FIG. FIG. 9 shows the results of measuring the swings of 300 or more golfers.

  As shown in FIG. 9, a correlation is not necessarily found between the swing tempo and the head speed (at the time of impact). Therefore, when classifying the swing characteristics of each golfer, it is necessary to consider both the swing tempo and the head speed.

  FIG. 10 is a diagram showing the relationship between the head speed and the frequency with a high SN ratio of the meat ratio for each shaft mass. The results shown in FIG. 10 are data having a population of about 90 general golfers. Referring to FIG. 10, when the shaft mass is 50 g, the frequency with a high S / N ratio becomes maximum when the head speed is 41 (m / s), and when the shaft mass is 60 g, the head speed is 43 (m / S), the frequency with a high S / N ratio becomes maximum, and when the shaft mass is 70 g, the frequency with a high S / N ratio becomes maximum when the head speed is 45 (m / s). In other words, a club shaft having a mass of about 50 g is suitable for a golfer having a head speed of about 41 (m / s), and a club shaft having a mass of about 60 g is suitable for a golfer having a head speed of about 43 (m / s). A club shaft with a mass of about 70 g is suitable for a golfer with a head speed of about 45 (m / s). Thus, a tendency that a club shaft having a large mass is suitable for a golfer having a high head speed can be seen.

  FIG. 11 is a diagram (first chart) for explaining the relationship between swing characteristics and preferable shaft mass, which is derived from the results of FIG. Referring to FIG. 11, the head speed of each golfer and the shaft mass suitable for the golfer do not completely correspond to each other, and in FIG. 11, a plurality of shaft masses (for example, 40 g and 50 g) are suitable. There are areas where the overlapping areas overlap. In this example, as shown in FIG. 11, about 90% of golfers could be covered by aligning the club shafts with masses of 40 g, 50 g, 60 g, 70 g, and 80 g.

  FIG. 12 is a diagram (second chart) for explaining the relationship between the swing characteristic and the preferable shaft condition. In FIG. 12, the “NORMAL” line indicates a line in which the relationship between the head speed and the swing tempo is an average level in a group of excellent golfers (for example, professional or handicap is single). Here, the “NORMAL” line is derived from the above excellent golfer head speed and swing tempo data by the method of least squares. Referring to FIG. 12, the shaft bending stiffness distribution needs to be separated from the standard as the swing characteristic is separated from the NORMAL line (in the directions of arrows DR3 and DR4). In FIG. 12, in the case of a golfer distributed between the STIFF line and the SOFT line (that is, a golfer having a good balance between the head speed and the swing tempo), a type having a standard bending stiffness distribution (hereinafter referred to as “bat”). A club shaft of “standard” is suitable, and in the case of a golfer distributed in the lower right of the STIFF line (that is, a golfer having a fast swing tempo for the head speed), the hand part is relatively hard ( A club shaft of “butt stiff” is suitable, and a golfer distributed in the upper left of the SOFT line (that is, a golfer having a slow swing tempo with respect to the head speed) has a relatively close hand portion. A soft type (hereinafter referred to as “Bat Soft”) club shaft is suitable. To have.

  FIG. 13 is a diagram (third chart) for explaining the relationship between the swing characteristic and the preferred flex. In FIG. 13, shaft flex suitable for each golfer (X flex (#X), S flex (#S), SR flex (#SR), R1 flex (# R1), R2 flex (# R2), L flex (#L)) is shown. Referring to FIG. 13, relatively hard golf club shafts (X flex, S flex, etc.) are suitable for golfers with high head speed and high swing tempo, with low head speed and swing tempo. A relatively soft golf club shaft (R2 flex, L flex, etc.) is suitable for a slow golfer.

  FIG. 14 is a diagram for explaining a method of classifying the shaft bending stiffness distribution (shaft condition). Referring to FIG. 14, the inventors of the present application calculated the ratio (TIP coefficient) of the average value of the bending rigidity value of the tip end portion of the shaft to the average value of the bending rigidity value of the shaft center portion, and the bending rigidity value of the shaft center portion. The shaft tone (bending stiffness distribution) was classified using the ratio (BUTT coefficient) of the bending stiffness value of the proximal portion of the shaft to the average value of the shaft. Here, the starting point is the average value of TIP coefficient and BUTT coefficient (TIP count: 0.54, BUTT coefficient: 2.0) of club shafts (about 150 types) sold in Japan, the US and Europe today. .

  In general, it is said that a fluctuation of 5% or less of the bending stiffness value is hardly felt. Accordingly, a range in which the BUTT coefficient is about 1.9 or more and 2.1 or less is classified as “first category”, the TIP coefficient is larger than about 0.54, and the BUTT coefficient is larger than about 2.1. Can be classified as “second category”, and a range in which the TIP coefficient is smaller than about 0.54 and the BUTT coefficient is smaller than about 1.9 can be classified as “third category”. The “first category” corresponds to a “bat standard” region in which the hardness of the hand portion is average (that is, the BUTT coefficient is about 1.9 or more and 2.1 or less). The “second category” is included in a region where the hand portion is relatively hard (that is, the BUTT coefficient is larger than about 2.1) and the tip portion is relatively hard. This area is referred to as a “butt stiff”. The “third category” is included in a region where the hand portion is relatively soft (that is, the BUTT coefficient is smaller than about 1.9) and the tip portion is relatively soft. This area is referred to as “bat soft”.

  In addition, the inventors of the present application, as golf club shafts to be selected, clubs of “Bat Soft”, “Bat Standard”, and “But Stiff” in which the relationship between the TIP coefficient and the BUT coefficient is distributed on an average line. A shaft (for example, “SOFT”, “STANDARD”, “STIFF” in FIG. 14) was prepared. In this way, the TIP coefficient can be determined simultaneously with the determination of the BUTT coefficient.

  “SOFT”, “STANDARD”, and “STIFF” shown in FIG. 14 are all designed to show the same amount of deflection in the cantilever beam model shown in FIG. The deformation of the club shaft during the swing is greatly influenced by bending on the hand side, and can be handled as a cantilever model as shown in FIG. As described above, the swing tempo can be uniformly evaluated regardless of which club shaft is used by making the same deflection amount in the cantilever model. In FIG. 15, the distance from the proximal fulcrum to the shaft tip: L1, the distance between fulcrums: L2, the distance from the shaft central fulcrum to the measurement point: L3, the distance between the measurement point and the load point: L4, and the load point The distance from the shaft tip to the shaft tip: L5 is, for example, L1 = 1020 (mm), L2 = 100 (mm), L3 = 833 (mm), L4 = 67 (mm), L5 = 20 (mm).

  FIG. 16 is a diagram illustrating the relationship between the swing characteristics and preferable shaft mass, flex, and shaft condition. In FIG. 16, preferable shaft mass (50 g, 60 g, 70 g, 80 g), flex, and shaft tone are overlapped for the swing characteristics (head speed and swing tempo).

In FIG. 16, in the case of a golfer having a swing characteristic of “G1”, 70 g or 80 g is suitable as the shaft mass, “SR” is suitable as the flex, and “Bat Soft” is suitable as the shaft condition. Yes. Therefore, in the case of the golfer, a trial hit is performed with a golf club having the club shafts 1 to 2 below, and the club shaft having the highest meet ratio SN ratio is selected.
1. Mass: 70 g, Flex: SR, Shaft condition: Batsoft Mass: 80 g, Flex: SR, Shaft condition: Bat soft In FIG. 16, in the case of a golfer having a swing characteristic of “G2”, 60 g or 70 g is suitable as the shaft mass, and “SR” is suitable as the flex. “But Standard” is suitable for shaft condition. Therefore, in the case of the golfer, a trial hit is performed with a golf club having the club shafts 1 to 2 below, and the club shaft having the highest meet ratio SN ratio is selected.
1. Mass: 60 g, Flex: SR, Shaft condition: Butt Standard Mass: 70 g, Flex: SR, Shaft condition: Bat standard In FIG. 16, in the case of a golfer having a swing characteristic of “G3”, 50 g or 60 g is suitable as the shaft mass, and “S” is used as the flex. “But stiff” is suitable as the shaft tone. Therefore, in the case of the golfer, a trial hit is performed with a golf club having the club shafts 1 to 2 below, and the club shaft having the highest meet ratio SN ratio is selected.
1. Mass: 50 g, Flex: S, Shaft condition: Butstiff Mass: 60 g, flex: S, shaft tone: butt stiff As described above, the shaft mass, flex, and bending stiffness distribution can be simultaneously selected from the head speed and swing tempo.

  Table 2 shows the types of golf club shafts prepared by the present inventors in carrying out the golf club shaft selection method according to the present embodiment.

  The type of club shaft necessary for carrying out the golf club shaft selection method according to the present embodiment is derived as follows. FIG. 17 is a view showing a range in which the “40 g” shaft is suitable and a portion showing a preferable shaft condition and flex are extracted from the description of FIG. 16. Referring to FIG. 17, when the shaft mass is 40 g, the region suitable for “Bat Soft” overlaps the region suitable for R2 Flex and R1 Flex, and the region suitable for “But Standard” includes R1 Flex and SR. The area where the flex is suitable and the area where the “butt stiff” is suitable overlaps the area where the R1 flex, SR flex and S flex are suitable. Thus, for a club shaft with a mass of 40 g, a “Batsoft” club shaft with a flex of R2 and R1 flex, a “Bat Standard” club shaft with a flex of R1 and SR flex, and a flex of R1 It is only necessary to prepare “butt stiff” club shafts which are flex, SR flex and S flex. Thus, all the types of club shafts necessary for carrying out the golf club shaft selection method according to the present embodiment are derived from FIG. In this example, by preparing a club shaft of the type shown in Table 2, approximately 90% of golfers could be covered.

  In the design of a golf club shaft, the shaft mass, shaft tone and flex can be adjusted independently of each other. Therefore, as shown in Table 2, when preparing 5 types of shaft mass, 3 types of shaft tone, and 5 types of flex club shafts, 75 (= 5 × 3 × 5) type club shafts are prepared. It will be. On the other hand, in this embodiment, as shown in Table 2, only about 90% of club shafts of 34 types (Bat soft: 11 type, Bat standard: 11 type, Butt stiff: 12 type) are prepared. The most suitable golf club shaft for golfers in Japan could be selected. Furthermore, in this embodiment, only by measuring the head speed and swing tempo of each golfer, the number of golf club shafts suitable for each golfer can be narrowed down to several (for example, two). As described above, according to the golf club shaft selection method according to the present embodiment, it is possible to appropriately select an optimum club shaft for each golfer from various types of club shafts by a simple method. In addition, as a result of each golfer performing a test shot using a plurality of actually selected club shafts, the inventors of the present application have found that at least one of the shafts has a sufficiently high SN ratio. Experiments have confirmed that the ratio is obtained.

  Although the embodiments and examples of the present invention have been described above, the embodiments and examples disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

1 is a block diagram showing a configuration of a golf club shaft selection system according to one embodiment of the present invention. It is the block diagram which showed the structure of the swing analysis apparatus shown by FIG. It is the figure which showed the motion of the golf club near the top of swing in a golf swing. It is the block diagram which showed the structure of the modification of the swing analyzer shown by FIG. It is the figure which showed the golf club used for the swing analysis in the swing analysis apparatus shown by FIG. It is a figure which shows the VI-VI cross section in FIG. It is a flowchart explaining the golf club shaft selection method which concerns on one embodiment of this invention. It is the figure which showed the outer diameter and bending rigidity distribution of the golf club shaft used for the golf club shaft selection method concerning one Example of this invention. It is a figure which shows distribution of the head speed detected by the detection step in the golf club shaft selection method which concerns on one Example of this invention, and swing tempo. It is the figure which showed the relationship between head speed and the frequency with a high SN ratio of meat ratio according to shaft mass. It is a figure (1st chart) explaining the relationship between a swing characteristic and preferable shaft mass. It is a figure (2nd chart) explaining the relationship between a swing characteristic and preferable shaft condition. It is the figure (3rd chart) which showed the relationship between a swing characteristic and a preferable flex. It is a figure explaining the classification method of shaft bending rigidity distribution. It is a figure explaining a cantilever model. It is a figure explaining the relationship between a swing characteristic and preferable shaft mass, a flex, and a shaft condition. It is the figure which extracted and showed the part which shows the preferable shaft condition and the flexure from the description of FIG. 16, and the shaft of "40g".

Explanation of symbols

1 Swing Analyzer, 1A, 1B High Speed Camera, 1C High Speed Video Tape Recorder, 1D Metahexalite, 1E Strobe Power Supply, 1F Strobe, 1G
Strain gauge, 1H bridge box, 1I amplifier, 2 golfer, 3 golf club, 4 ball, 5 club shaft, 10G to 13G strain gauge application position, 100 head speed detection unit, 200 swing tempo detection unit, 300 chart, 310 1st Chart, 320 Second chart, 330 Third chart, 400 Shaft selection unit, 500 Display device.

Claims (6)

A head speed detecting means for detecting a head speed at the time of impact in a golfer's swing;
Swing tempo detection means for detecting the swing tempo of the golfer based on the maximum deflection amount of the shaft in the golfer's swing;
A chart showing a preferred shaft tone according to the head speed and the swing tempo;
A selecting means for selecting a golf club shaft suitable for the golfer based on the head speed and the swing tempo detected by the head speed detecting means and the swing tempo detecting means, with reference to the chart;
E Bei and display means for displaying a golf club shaft which is selected by said selecting means,
The shaft tone classification in the chart includes the average value of the bending rigidity value of the central portion of the shaft of the golf club shaft and the bending rigidity value of the club shaft at the tip portion located on the club head side with respect to the central portion of the shaft. This is performed based on the relationship between the average value and the average value of the bending rigidity value of the club shaft at the hand portion located on the grip side with respect to the shaft center part, and the average value of the bending rigidity value of the shaft center part is A golf club shaft selection system , which is performed using a ratio of an average value of the bending rigidity value of the tip end part and a ratio of an average value of the bending rigidity value of the proximal part to the average value of the bending rigidity value of the central part of the shaft. . A head speed detecting means for detecting a head speed at the time of impact in a golfer's swing;
Swing tempo detection means for detecting the swing tempo of the golfer based on the maximum deflection amount of the shaft in the golfer's swing;
A first chart showing a preferred shaft mass according to the head speed and the swing tempo;
A second chart showing a preferred shaft condition according to the head speed and the swing tempo;
Selection means for selecting a golf club shaft suitable for the golfer based on the head speed and the swing tempo detected by the head speed detection means and the swing tempo detection means with reference to the first and second charts. When,
E Bei and display means for displaying a golf club shaft which is selected by said selecting means,
The classification of the shaft tone in the second chart includes the average value of the bending rigidity value of the central portion of the shaft of the golf club shaft and the bending rigidity of the club shaft at the tip portion located on the club head side with respect to the central portion of the shaft. The average value of the bending stiffness value of the club shaft at the grip portion with respect to the central portion of the shaft, and the average bending stiffness value of the central portion of the shaft. The ratio of the average value of the bending rigidity value of the tip part to the value and the ratio of the average value of the bending rigidity value of the proximal part to the average value of the bending rigidity value of the central part of the shaft Selection system. Further comprising another chart showing a preferred flex depending on the head speed and the swing tempo,
The golf club shaft selection system according to claim 1 , wherein the selection unit refers to the other chart when selecting a golf club shaft suitable for the golfer. Detecting a head speed at impact in a golfer's swing and a swing tempo of the golfer;
E Bei a step of selecting a golf club shaft having a kick point of classification suitable for the golfer based on a detection result by said detection step,
The swing tempo is detected based on the maximum deflection amount of the shaft in the golfer's swing,
The shaft tones are classified into an average value of a bending rigidity value at a central portion of the shaft of the golf club shaft, and an average value of a bending rigidity value of the club shaft at a tip portion located on the club head side with respect to the central portion of the shaft. The tip end portion with respect to the average value of the bending rigidity value of the central portion of the shaft is performed based on the relationship with the average value of the bending rigidity value of the club shaft at the hand portion located on the grip side with respect to the central portion of the shaft. A method for selecting a golf club shaft , which is performed using a ratio of an average value of the bending stiffness of the shaft and a ratio of an average value of the bending rigidity value of the proximal portion to the average value of the bending stiffness value of the central portion of the shaft. Detecting a head speed at impact in a golfer's swing and a swing tempo of the golfer;
E Bei a step of selecting a golf club shaft having a kick point of categories suited to the shaft mass and the golfer suitable to the golfer on the basis of the detection result by the detecting step,
The swing tempo is detected based on the maximum deflection amount of the shaft in the golfer's swing,
The shaft tones are classified into an average value of a bending rigidity value at a central portion of the shaft of the golf club shaft, and an average value of a bending rigidity value of the club shaft at a tip portion located on the club head side with respect to the central portion of the shaft. The tip end portion with respect to the average value of the bending rigidity value of the central portion of the shaft is performed based on the relationship with the average value of the bending rigidity value of the club shaft at the hand portion located on the grip side with respect to the central portion of the shaft. A method for selecting a golf club shaft , which is performed using a ratio of an average value of the bending stiffness of the shaft and a ratio of an average value of the bending rigidity value of the proximal portion to the average value of the bending stiffness value of the central portion of the shaft. 6. The golf club shaft selection method according to claim 4 , wherein the selecting step includes a step of selecting a golf club shaft having a flex suitable for the golfer based on a detection result obtained by the detecting step.

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